The type of method adopted for the evaluation of drug-induced kidney injury (DIKI) plays an important role during the drug discovery process. In the present study, the usefulness of cultured rat kidney tissue slices maintained on gas-permeable poly(dimethylsiloxane) (PDMS) plates for DIKI was assessed by monitoring the ATP content as a marker of cell viability. The amount of ATP in the kidney slices cultured on the PDMS plates was higher than that in the slices cultured on gas-impermeable polystyrene plates. The protein expression of organic cation transporter-2 (Oct2) was maintained for 3 d. Cisplatin showed a time- and concentration-dependent reduction in ATP in the slices with a half-effective concentration value of 24 µM, which was alleviated by cimetidine, an Oct2 inhibitor, suggesting that cisplatin-induced kidney injury in the cultured slices was regulated by the basolateral uptake transporter Oct2. Furthermore, the intensity of platinum anticancer drug-induced nephrotoxicity in the cultured slices was consistent with that of the in vivo study. In conclusion, the primary culture of rat kidney tissue slices on gas-permeable plates is expected to aid in the prediction of the extent of nephrotoxicity of drugs, even when transporters are responsible for the accumulation of drugs in kidney tissues.
Keywords: cisplatin; drug-induced kidney injury (DIKI); gas-permeable plate; kidney; toxicity; transporter.